package main

import (
	"context"
	"log/slog"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/joho/godotenv"

	httpadapter "gitea.nik4nao.com/nik/home-services/alert-bridge/internal/adapters/primary/http"
	"gitea.nik4nao.com/nik/home-services/alert-bridge/internal/adapters/secondary/discordwebhook"
	"gitea.nik4nao.com/nik/home-services/alert-bridge/internal/app"
	"gitea.nik4nao.com/nik/home-services/alert-bridge/internal/config"
	"gitea.nik4nao.com/nik/home-services/alert-bridge/internal/logger"
	"gitea.nik4nao.com/nik/home-services/alert-bridge/internal/telemetry"
)

var version = "dev"

func main() {
	_ = godotenv.Load()

	cfg, err := config.Load()
	if err != nil {
		os.Stderr.WriteString("config error: " + err.Error() + "\n")
		os.Exit(1)
	}

	log := logger.New(cfg.LogFormat, cfg.LogLevel)
	slog.SetDefault(log)
	log.Info("starting alert-bridge",
		"version", version,
		"http_port", cfg.HTTPPort,
		"log_level", cfg.LogLevel,
		"log_format", cfg.LogFormat,
	)

	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
	defer stop()
	ctx = logger.WithLogger(ctx, log)

	shutdown, err := telemetry.Setup(ctx, "alert-bridge", version, cfg)
	if err != nil {
		log.Error("telemetry setup failed", "err", err)
		os.Exit(1)
	}
	if cfg.OTELEndpoint != "" {
		log.Info("telemetry enabled", "endpoint", cfg.OTELEndpoint)
	} else {
		log.Debug("telemetry disabled")
	}

	notifier := discordwebhook.New(cfg.DiscordWebhookURL, cfg.MentionUserID)
	alertApp := app.NewAlertApp(notifier)
	alertHandler := httpadapter.NewHandler(alertApp, cfg.APIKey)

	mux := http.NewServeMux()
	mux.Handle("POST /alerts", alertHandler)
	mux.HandleFunc("GET /healthz", func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	})

	srv := &http.Server{
		Addr:              ":" + cfg.HTTPPort,
		Handler:           mux,
		ReadHeaderTimeout: 5 * time.Second,
	}

	go func() {
		log.Info("alert-bridge listening", "addr", srv.Addr)
		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Error("serve failed", "err", err)
		}
	}()

	<-ctx.Done()
	log.Info("shutdown signal received, draining")

	shutdownCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	if err := srv.Shutdown(shutdownCtx); err != nil {
		log.Error("http server shutdown failed", "err", err)
	}
	log.Info("shutdown complete")

	if err := shutdown(context.Background()); err != nil {
		log.Error("telemetry shutdown error", "err", err)
	}
}